College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China.
Institute of Plant Protection, Shandong Academy of Agricultural Sciences, Jinan 250100, China.
Int J Mol Sci. 2024 Oct 17;25(20):11145. doi: 10.3390/ijms252011145.
Heavy metal pollution is a serious global environmental issue. It threatens human and ecological health. Heavy metals can accumulate in the soil over extended periods and inevitably transfer through the food chain to herbivorous insects and their natural enemies, leading to various adverse effects. This study aimed to investigate the stress responses and biochemical metabolic changes of aphids and one of aphids' predators, ladybugs, under cadmium (Cd) and lead (Pb) stress by constructing a food chain of L., , and . The results showed that aphids and ladybugs had a notable accumulation of Cd and Pb. Insects can adapt to heavy metal stress by regulating their energy metabolism pathways. Glycogen content in the first filial generation (F1) aphids decreased significantly, glucose content in the second filial generation (F2) to the fourth filial generation (F4) adult aphids significantly increased, and trehalose content in the F1 adult aphids increased significantly. Moreover, the relative expression levels of trehalase () and trehalose-6-phosphate synthase () in the F1 adult aphids were significantly higher than those in the control group, and the expression levels of genes in the second filial generation to the fifth filial generation (F2 to F5) aphids decreased, suggesting that insects can resist heavy metal stress by regulating trehalose metabolism. The fertility of female aphids in all treatment groups was reduced compared to the control group. Additionally, the relative expression level of vitellogenin () was down-regulated in all aphid generations except the F1 aphids. There was interaction between heavy metal concentration and aphid generation, and it significantly affected the number of aphids' offspring and the expression of the aphid gene. The developmental duration of the ladybugs from the second to fourth instars was prolonged, and the weight decreased significantly from the prepupa to the adult stages. These results contribute to understanding the effects of Cd-Pb accumulation on phytophagous insects and higher trophic levels' natural enemies, laying the foundation for protecting natural enemies and maintaining ecosystem stability.
重金属污染是一个严重的全球性环境问题，它威胁着人类和生态健康。重金属可以在土壤中长时间积累，并通过食物链不可避免地转移到草食性昆虫及其天敌身上，导致各种不利影响。本研究通过构建 L.、、和的食物链，旨在探讨镉（Cd）和铅（Pb）胁迫下蚜虫和蚜虫天敌之一瓢虫的应激反应和生化代谢变化。结果表明，蚜虫和瓢虫对 Cd 和 Pb 有明显的积累。昆虫可以通过调节能量代谢途径来适应重金属胁迫。第一代（F1）蚜虫的糖原含量显著降低，第二代至第四代（F2 至 F4）成虫蚜虫的葡萄糖含量显著增加，F1 成虫蚜虫的海藻糖含量显著增加。此外，F1 成虫蚜虫的海藻糖酶（）和海藻糖-6-磷酸合酶（）相对表达水平显著高于对照组，第二代至第五代（F2 至 F5）蚜虫的基因表达水平降低，表明昆虫可以通过调节海藻糖代谢来抵抗重金属胁迫。与对照组相比，所有处理组的雌性蚜虫的繁殖力均降低。此外，除第一代蚜虫外，所有蚜虫世代的卵黄蛋白原（）相对表达水平均下调。重金属浓度与蚜虫世代之间存在互作，显著影响蚜虫后代数量和蚜虫基因的表达。瓢虫从第二到第四龄的发育时间延长，从预蛹到成虫阶段的体重显著下降。这些结果有助于了解 Cd-Pb 积累对植食性昆虫和更高营养级别的天敌的影响，为保护天敌和维持生态系统稳定奠定了基础。
